Tool for perforating corrugated material.



C. A. ELIGH.

TOOL FOR PERFORMING CORRUGATED MATERIAL.

APPLICATION FILED NOV. 4. I915.

Patented June 5, 1917.

'rugated.

CHARLES A. ELIGH, OF DETROIT, MICHIGAN, ASSIGNOR TO LONG MANUFACTURING COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

' Specification of Letters Patent.

Patented June 5, 1917.

Application filed November 4, 1915. Serial No. 59,531.

To all whom it may concern:

Be it known that I, CHARLES A. ELIGH, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Tools for Perforating Corrugated Material, of which the following is a full, clear, and exact descrlption.

In my co-pending application, S. N. 17852, I showed a radiating fin formed from a fiat straight strip of metal and curved in its own planeby corrugation, the corrugations d1- minishing in depth from one edge toward the other. In my co-pending application S. N. @5285, I describe the method of making said fins, one step of the method being that of perforating the fin after it has been cor- As shown in said applications the perforations are placed indiscriminately with reference to the corrugations. For example, in S. N. 17852 the apertures 26 are oval and cross corrugations more or less. It is evident that to form these apertures without flattening or otherwise distorting the corrugations, which would probably result in changing the curvature of the fin, it is necessary to support the metal and retain it in its corrugated state while the metal is pierced. For this purpose I have designed the novel tool shown in the accompanylng drawings, in which:

Figure 1 is an elevation with a small portion broken away at one point.

Fig. 2 is a plan of the lower, portion of the tool; 93. 6., the portion seen below line 2-2 in Fig. 1.

Fig. 3 is a sectional view on line 3-3 Fig. 1.

Fig. 4 shows a fin after it has been perforated, and shows indiscriminate relationship between the corrugations and perforations. The converging lines may be taken to indicate corrugations. That is, each line may be considered the bottom of a corrugation.

Fig. 5 is a modification in which the punch merely pierces the metal, the displaced metal remaining as a bur around the edge of the aperture.

Similar numerals refer to like parts in all of the views.

Upon the base 10 a stripper plate 11 is mounted upon compression springs 12. The desired number of punches 13 are fixed in the base and extend upward through holes in the stripper plate, the ends of the punches being below the upper surface of the plate when it is in normal position as in Figs. 1 and 3. A top plate 14 is placed above the stripper plate and is connected to, or rather held in position with reference to the base by guide pins 15 which slideup and down in holes 16 in the base. A die 17 is secured to the under side of the top plate. In fact it is preferable to have the die and top plate integral, and the drawings show this construction. The die is provided with apertures to register with the punches, said apertures extending through the top plate as well. It is understood, of course, that this tool is placed in a punch press, which, being an article in ordinary use need not be illustrated. The base 10 is secured to the bed of the press and the top plate to the ram which is arranged to reciprocate perpendicularly to the bed.

The face of the die is corrugated just like the fin; that is it has corrugations complementary to those of the fin. The surface of the stripper plate is also corrugated. The fin is laid upon the stripper plate, a frame 18 acting as a guide to locate the fin, and as.

the ram descends the die is brought down on the fin, the fin then being confined between the two corrugated surfaces. Continued downward movement of the ram carries the top and stripper plates downward, the latter moving in opposition to the springs 12. As the punches are stationary the fin is forced down upon their ends, the corners of which, being sharp and coacting with the sharp corners of the apertures in the die, act as shears and shear out pieces of the fin, thus forming the perforations seen in the fin in Fig. 4:. As the fin is confined between the two corrugated plates it is not distorted, and the edges of the apertures are left smooth and regular. As the die rises the springs force the stripper plate to follow it keeping the fin confined until the punches have been entirely withdrawn from the fin. Nhen the stripper reaches its limit of movement it comes to rest and the die continues upward, releasing the fin.

While the best results are obtained by confining the fin between two corrugated plates, good results may be obtained with the die only corrugated, the stripper plate being flat. or, the Hat stripper plateinay have pins scattered over its surface to enter the fin corrugations and act as a sort of substi 'tute "for thecorrugated surface. Another modification is illustrated in Fig. 5 in which the punch 19 is pointedand does not shear the metal, In this netliod' the metal dis" placed to form the aperture is not entirely removed but is carried up into the die in 'finafter it is finished, T he punch is slightly Q-hsmaller than the hole in the die to leave room o for this bur. Other modifications might be made by a skilled mechanic assisted by the instruction herein given.

iVhat I claim is asfollows:

7 11'A tool for. perforating material, comprising a die Whose surface has corrugations complementary to the corrugations of the material to be perforated and havingapertures' located ndiscriminately with reference tothe corrugations; punches adapted to pass through the material, into said apertures,

thereby perforating the materiahand pressing means independent of the punches for pressing the material against the die, said pressing nie'ans being constructed with auxil- Copies of this patent may be obtained for iary'i provisions for maintaining substantially'invariable pressure during the entire the form of a burQO, which IGHIELiIIS'OIT the.

having apertures located indiscriminately Wll3l1 reference to and extending over one or more corrugations indiscriminately the edges of said apertures being adapted to act as shears, and punches having edges to cooper ate with the edges of the apertures and shear perforations in the material lying upon the corrugated surface. I

3. A tool for perforating corrugated material, comprising a die Whosesurface has corrugations complementary to the corrugati ons of the material tobe perforated and having apertures which extend over tWo or more corrugations; and punches adapted to pass through the material into said apertures, thereby perforating the material. I In testimony whereof I afiix mysignature in the presence of two subscribing witnesses.

. CHARLES A. ELIGH.

Witnesses JL. DRYDEN, 7 WV. F, BUBGEN. i

five cents each" by, addressing the Commissioner of Patents,

Washington, 13.6. a a y 

